9,326 research outputs found
Strategic Port Graph Rewriting: An Interactive Modelling and Analysis Framework
We present strategic portgraph rewriting as a basis for the implementation of
visual modelling and analysis tools. The goal is to facilitate the
specification, analysis and simulation of complex systems, using port graphs. A
system is represented by an initial graph and a collection of graph rewriting
rules, together with a user-defined strategy to control the application of
rules. The strategy language includes constructs to deal with graph traversal
and management of rewriting positions in the graph. We give a small-step
operational semantics for the language, and describe its implementation in the
graph transformation and visualisation tool PORGY.Comment: In Proceedings GRAPHITE 2014, arXiv:1407.767
SAGA: A project to automate the management of software production systems
The Software Automation, Generation and Administration (SAGA) project is investigating the design and construction of practical software engineering environments for developing and maintaining aerospace systems and applications software. The research includes the practical organization of the software lifecycle, configuration management, software requirements specifications, executable specifications, design methodologies, programming, verification, validation and testing, version control, maintenance, the reuse of software, software libraries, documentation, and automated management
Efficient Analysis of Complex Diagrams using Constraint-Based Parsing
This paper describes substantial advances in the analysis (parsing) of
diagrams using constraint grammars. The addition of set types to the grammar
and spatial indexing of the data make it possible to efficiently parse real
diagrams of substantial complexity. The system is probably the first to
demonstrate efficient diagram parsing using grammars that easily be retargeted
to other domains. The work assumes that the diagrams are available as a flat
collection of graphics primitives: lines, polygons, circles, Bezier curves and
text. This is appropriate for future electronic documents or for vectorized
diagrams converted from scanned images. The classes of diagrams that we have
analyzed include x,y data graphs and genetic diagrams drawn from the biological
literature, as well as finite state automata diagrams (states and arcs). As an
example, parsing a four-part data graph composed of 133 primitives required 35
sec using Macintosh Common Lisp on a Macintosh Quadra 700.Comment: 9 pages, Postscript, no fonts, compressed, uuencoded. Composed in
MSWord 5.1a for the Mac. To appear in ICDAR '95. Other versions at
ftp://ftp.ccs.neu.edu/pub/people/futrell
Extraction of UML class diagrams from natural language specifications
Dans lâingĂ©nierie dirigĂ©e par modĂšle, les diagrammes de classes UML servent Ă la planification
et Ă la communication entre les diffĂ©rents acteurs dâun projet logiciel. Dans ce mĂ©moire,
nous proposons une mĂ©thode automatique pour lâextraction des diagrammes de classes UML
à partir de spécifications en langues naturelles. Pour développer notre méthode, nous créons
un dépÎt de diagrammes de classes UML et de leurs spécifications en anglais fournies par
des bĂ©nĂ©voles. Notre processus dâextraction se fait en plusieurs Ă©tapes: la segmentation
des spécifications en phrases, la classification de ces phrases, la génération des fragments de
diagrammes de classes UML Ă partir de chaque phrase, et la composition de ces fragments en
un diagramme de classes UML. Nous avons validĂ© notre approche dâextraction en utilisant
le dĂ©pĂŽt de paires diagramme-spĂ©cification. MĂȘme si les rĂ©sultats obtenus montrent une
prĂ©cision et un rappel bas, notre travail a permis dâidentifier les Ă©lĂ©ments qui peuvent ĂȘtre
améliorés pour une meilleure extraction.In model-driven engineering, UML class diagrams serve as a way to plan and communicate
between developers. In this thesis, we propose an automated approach for the extraction of
UML class diagrams from natural language software specifications. To develop our approach,
we create a dataset of UML class diagrams and their English specifications with the help of
volunteers. Our approach is a pipeline of steps consisting of the segmentation of the input into
sentences, the classification of the sentences, the generation of UML class diagram fragments
from sentences, and the composition of these fragments into one UML class diagram. We
develop a quantitative testing framework specific to UML class diagram extraction. Our
approach yields low precision and recall but serves as a benchmark for future research
An Abstract Machine for Unification Grammars
This work describes the design and implementation of an abstract machine,
Amalia, for the linguistic formalism ALE, which is based on typed feature
structures. This formalism is one of the most widely accepted in computational
linguistics and has been used for designing grammars in various linguistic
theories, most notably HPSG. Amalia is composed of data structures and a set of
instructions, augmented by a compiler from the grammatical formalism to the
abstract instructions, and a (portable) interpreter of the abstract
instructions. The effect of each instruction is defined using a low-level
language that can be executed on ordinary hardware.
The advantages of the abstract machine approach are twofold. From a
theoretical point of view, the abstract machine gives a well-defined
operational semantics to the grammatical formalism. This ensures that grammars
specified using our system are endowed with well defined meaning. It enables,
for example, to formally verify the correctness of a compiler for HPSG, given
an independent definition. From a practical point of view, Amalia is the first
system that employs a direct compilation scheme for unification grammars that
are based on typed feature structures. The use of amalia results in a much
improved performance over existing systems.
In order to test the machine on a realistic application, we have developed a
small-scale, HPSG-based grammar for a fragment of the Hebrew language, using
Amalia as the development platform. This is the first application of HPSG to a
Semitic language.Comment: Doctoral Thesis, 96 pages, many postscript figures, uses pstricks,
pst-node, psfig, fullname and a macros fil
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